They gonna keep on throwing in tag team matches on RAW/SD anyway, i see no harm in debuting the tag titles for that.
And if Nia is not here for it, then keep her away from the title. I am sure 99% of the girls want to have a run with it so she can wait.

They can't bring in the 'Sluts and Hoes' storylines like they used to because WWE is PG.
The best storyline for me imo is Trish/Vince/Stephanie and for that I don't see it happening ever again. (Sable/Vince/Steph or Torrie/Torrie's dad/Dawn Marie etc)
So now they are only left with Friendship/Jealousy feuds.
The next best angle / feud that wouldn't 'disrupt' the PG thingy should probably be a similarity of the storyline of Trish/Jericho/Lita/Christian.

If they intend to bring in the tag titles for Evolution, I can see them teaming Nikki and Brie together instead of giving them each single matches. It might end up with Trish and Lita vs Bella Twins vs iiconics vs Mickie and Alexa (and maybe Laycool since Michelle is rumored to be on) for the tag titles.
That will reduce the amount of single matches while showcasing more girls on the ppv. Anyway, I still think the Bellas came back to get ready for the debut of the tag titles tbh.
Charlotte will probably face Becky
Ronda might face Natalya(heel turn few weeks before Evolution)
Nia vs Beth?
And a random gauntlet match or something for the rest.

I love how Trish and Charlotte didn't come from the indies and both of them made history. Poor indy girls ha.
Anyway it's natural that Charlotte is breaking records and making history. I mean if it's not her, then who? I really can't think of someone who is more well balanced in terms of in ring skills, mic skills, looks, presence etc.